#include "node_dtrace.h"

#ifdef HAVE_DTRACE
#include "node_provider.h"
#elif HAVE_ETW
#include "node_win32_etw_provider.h"
#include "node_win32_etw_provider-inl.h"
#else
#define NODE_HTTP_SERVER_REQUEST(arg0, arg1, arg2, arg3, arg4, arg5, arg6)
#define NODE_HTTP_SERVER_REQUEST_ENABLED() (0)
#define NODE_HTTP_SERVER_RESPONSE(arg0, arg1, arg2, arg3)
#define NODE_HTTP_SERVER_RESPONSE_ENABLED() (0)
#define NODE_HTTP_CLIENT_REQUEST(arg0, arg1, arg2, arg3, arg4, arg5, arg6)
#define NODE_HTTP_CLIENT_REQUEST_ENABLED() (0)
#define NODE_HTTP_CLIENT_RESPONSE(arg0, arg1, arg2, arg3)
#define NODE_HTTP_CLIENT_RESPONSE_ENABLED() (0)
#define NODE_NET_SERVER_CONNECTION(arg0, arg1, arg2, arg3)
#define NODE_NET_SERVER_CONNECTION_ENABLED() (0)
#define NODE_NET_STREAM_END(arg0, arg1, arg2, arg3)
#define NODE_NET_STREAM_END_ENABLED() (0)
#define NODE_GC_START(arg0, arg1, arg2)
#define NODE_GC_DONE(arg0, arg1, arg2)
#endif

#include "env.h"
#include "env-inl.h"

#include "util.h"

#include <string.h>

namespace node {

using v8::FunctionCallbackInfo;
using v8::GCCallbackFlags;
using v8::GCType;
using v8::HandleScope;
using v8::Isolate;
using v8::Local;
using v8::Object;
using v8::String;
using v8::Value;

#define SLURP_STRING(obj, member, valp)                                        \
    if (!(obj)->IsObject()) {                                                  \
        return env->ThrowError(                                                \
            "expected object for " #obj " to contain string member " #member); \
    }                                                                          \
    node::Utf8Value _##member(env->isolate(),                                  \
        obj->Get(OneByteString(env->isolate(), #member)));                     \
    if ((*(const char**)valp = *_##member) == nullptr)                         \
        *(const char**)valp = "<unknown>";

#define SLURP_INT(obj, member, valp)                                            \
    if (!(obj)->IsObject()) {                                                   \
        return env->ThrowError(                                                 \
            "expected object for " #obj " to contain integer member " #member); \
    }                                                                           \
    *valp = obj->Get(OneByteString(env->isolate(), #member))                    \
                ->ToInteger(env->isolate())                                     \
                ->Value();

#define SLURP_OBJECT(obj, member, valp)                                        \
    if (!(obj)->IsObject()) {                                                  \
        return env->ThrowError(                                                \
            "expected object for " #obj " to contain object member " #member); \
    }                                                                          \
    *valp = Local<Object>::Cast(obj->Get(OneByteString(env->isolate(), #member)));

#define SLURP_CONNECTION(arg, conn)                                                          \
    if (!(arg)->IsObject()) {                                                                \
        return env->ThrowError(                                                              \
            "expected argument " #arg " to be a connection object");                         \
    }                                                                                        \
    node_dtrace_connection_t conn;                                                           \
    Local<Object> _##conn = Local<Object>::Cast(arg);                                        \
    Local<Value> _handle = (_##conn)->Get(FIXED_ONE_BYTE_STRING(env->isolate(), "_handle")); \
    if (_handle->IsObject()) {                                                               \
        SLURP_INT(_handle.As<Object>(), fd, &conn.fd);                                       \
    } else {                                                                                 \
        conn.fd = -1;                                                                        \
    }                                                                                        \
    SLURP_STRING(_##conn, remoteAddress, &conn.remote);                                      \
    SLURP_INT(_##conn, remotePort, &conn.port);                                              \
    SLURP_INT(_##conn, bufferSize, &conn.buffered);

#define SLURP_CONNECTION_HTTP_CLIENT(arg, conn)                      \
    if (!(arg)->IsObject()) {                                        \
        return env->ThrowError(                                      \
            "expected argument " #arg " to be a connection object"); \
    }                                                                \
    node_dtrace_connection_t conn;                                   \
    Local<Object> _##conn = Local<Object>::Cast(arg);                \
    SLURP_INT(_##conn, fd, &conn.fd);                                \
    SLURP_STRING(_##conn, host, &conn.remote);                       \
    SLURP_INT(_##conn, port, &conn.port);                            \
    SLURP_INT(_##conn, bufferSize, &conn.buffered);

#define SLURP_CONNECTION_HTTP_CLIENT_RESPONSE(arg0, arg1, conn)       \
    if (!(arg0)->IsObject()) {                                        \
        return env->ThrowError(                                       \
            "expected argument " #arg0 " to be a connection object"); \
    }                                                                 \
    if (!(arg1)->IsObject()) {                                        \
        return env->ThrowError(                                       \
            "expected argument " #arg1 " to be a connection object"); \
    }                                                                 \
    node_dtrace_connection_t conn;                                    \
    Local<Object> _##conn = Local<Object>::Cast(arg0);                \
    SLURP_INT(_##conn, fd, &conn.fd);                                 \
    SLURP_INT(_##conn, bufferSize, &conn.buffered);                   \
    _##conn = Local<Object>::Cast(arg1);                              \
    SLURP_STRING(_##conn, host, &conn.remote);                        \
    SLURP_INT(_##conn, port, &conn.port);

void DTRACE_NET_SERVER_CONNECTION(const FunctionCallbackInfo<Value>& args)
{
    if (!NODE_NET_SERVER_CONNECTION_ENABLED())
        return;
    Environment* env = Environment::GetCurrent(args);
    SLURP_CONNECTION(args[0], conn);
    NODE_NET_SERVER_CONNECTION(&conn, conn.remote, conn.port, conn.fd);
}

void DTRACE_NET_STREAM_END(const FunctionCallbackInfo<Value>& args)
{
    if (!NODE_NET_STREAM_END_ENABLED())
        return;
    Environment* env = Environment::GetCurrent(args);
    SLURP_CONNECTION(args[0], conn);
    NODE_NET_STREAM_END(&conn, conn.remote, conn.port, conn.fd);
}

void DTRACE_HTTP_SERVER_REQUEST(const FunctionCallbackInfo<Value>& args)
{
    node_dtrace_http_server_request_t req;

    if (!NODE_HTTP_SERVER_REQUEST_ENABLED())
        return;

    Environment* env = Environment::GetCurrent(args);
    HandleScope scope(env->isolate());
    Local<Object> arg0 = Local<Object>::Cast(args[0]);
    Local<Object> headers;

    memset(&req, 0, sizeof(req));
    req._un.version = 1;
    SLURP_STRING(arg0, url, &req.url);
    SLURP_STRING(arg0, method, &req.method);
    SLURP_OBJECT(arg0, headers, &headers);

    if (!(headers)->IsObject()) {
        return env->ThrowError(
            "expected object for request to contain string member headers");
    }

    Local<Value> strfwdfor = headers->Get(env->x_forwarded_string());
    node::Utf8Value fwdfor(env->isolate(), strfwdfor);

    if (!strfwdfor->IsString() || (req.forwardedFor = *fwdfor) == nullptr)
        req.forwardedFor = const_cast<char*>("");

    SLURP_CONNECTION(args[1], conn);
    NODE_HTTP_SERVER_REQUEST(&req, &conn, conn.remote, conn.port, req.method,
        req.url, conn.fd);
}

void DTRACE_HTTP_SERVER_RESPONSE(const FunctionCallbackInfo<Value>& args)
{
    if (!NODE_HTTP_SERVER_RESPONSE_ENABLED())
        return;
    Environment* env = Environment::GetCurrent(args);
    SLURP_CONNECTION(args[0], conn);
    NODE_HTTP_SERVER_RESPONSE(&conn, conn.remote, conn.port, conn.fd);
}

void DTRACE_HTTP_CLIENT_REQUEST(const FunctionCallbackInfo<Value>& args)
{
    node_dtrace_http_client_request_t req;
    char* header;

    if (!NODE_HTTP_CLIENT_REQUEST_ENABLED())
        return;

    Environment* env = Environment::GetCurrent(args);
    HandleScope scope(env->isolate());

    /*
   * For the method and URL, we're going to dig them out of the header.  This
   * is not as efficient as it could be, but we would rather not force the
   * caller here to retain their method and URL until the time at which
   * DTRACE_HTTP_CLIENT_REQUEST can be called.
   */
    Local<Object> arg0 = Local<Object>::Cast(args[0]);
    SLURP_STRING(arg0, _header, &header);

    req.method = header;

    while (*header != '\0' && *header != ' ')
        header++;

    if (*header != '\0')
        *header++ = '\0';

    req.url = header;

    while (*header != '\0' && *header != ' ')
        header++;

    *header = '\0';

    SLURP_CONNECTION_HTTP_CLIENT(args[1], conn);
    NODE_HTTP_CLIENT_REQUEST(&req, &conn, conn.remote, conn.port, req.method,
        req.url, conn.fd);
}

void DTRACE_HTTP_CLIENT_RESPONSE(const FunctionCallbackInfo<Value>& args)
{
    if (!NODE_HTTP_CLIENT_RESPONSE_ENABLED())
        return;
    Environment* env = Environment::GetCurrent(args);
    SLURP_CONNECTION_HTTP_CLIENT_RESPONSE(args[0], args[1], conn);
    NODE_HTTP_CLIENT_RESPONSE(&conn, conn.remote, conn.port, conn.fd);
}

void dtrace_gc_start(Isolate* isolate, GCType type, GCCallbackFlags flags)
{
    // Previous versions of this probe point only logged type and flags.
    // That's why for reasons of backwards compatibility the isolate goes last.
    NODE_GC_START(type, flags, isolate);
}

void dtrace_gc_done(Isolate* isolate, GCType type, GCCallbackFlags flags)
{
    // Previous versions of this probe point only logged type and flags.
    // That's why for reasons of backwards compatibility the isolate goes last.
    NODE_GC_DONE(type, flags, isolate);
}

void InitDTrace(Environment* env, Local<Object> target)
{
    HandleScope scope(env->isolate());

    static struct {
        const char* name;
        void (*func)(const FunctionCallbackInfo<Value>&);
    } tab[] = {
#define NODE_PROBE(name) #name, name
        { NODE_PROBE(DTRACE_NET_SERVER_CONNECTION) },
        { NODE_PROBE(DTRACE_NET_STREAM_END) },
        { NODE_PROBE(DTRACE_HTTP_SERVER_REQUEST) },
        { NODE_PROBE(DTRACE_HTTP_SERVER_RESPONSE) },
        { NODE_PROBE(DTRACE_HTTP_CLIENT_REQUEST) },
        { NODE_PROBE(DTRACE_HTTP_CLIENT_RESPONSE) }
#undef NODE_PROBE
    };

    for (size_t i = 0; i < arraysize(tab); i++) {
        Local<String> key = OneByteString(env->isolate(), tab[i].name);
        Local<Value> val = env->NewFunctionTemplate(tab[i].func)->GetFunction();
        target->Set(key, val);
    }

#ifdef HAVE_ETW
    init_etw();
#endif

#if defined HAVE_DTRACE || defined HAVE_ETW
    env->isolate()->AddGCPrologueCallback(dtrace_gc_start);
    env->isolate()->AddGCEpilogueCallback(dtrace_gc_done);
#endif
}

} // namespace node
